Debian 9 Failed to mount Mount unit for core

HI,
First of all, Happy New Year to everyone !

I’m trying to install snapd on Debian 9 (Strech) but i have this error
after commands :

snap install core
gives error :
error: cannot perform the following tasks:

  • Mount snap “core” (10577) ([start snap-core-10577.mount] failed with exit status 1: Job for snap-core-10577.mount failed.
    See “systemctl status snap-core-10577.mount” and “journalctl -xe” for details.
    )

and then with

systemctl status snap-core-10577.mount
journalctl -xe

i can see :

“Failed to mount Mount unit for core”

Is it a kernel problem on which i can’t use/install snapd ?

Thanks for your help,
Best Regards
Pascall